In order to verify the vintage capacitor collection I slowly attained all perform to spec, I started to look for capacitor analyzers. The most well known is the Sprague TEL-OHMIKE series. Trying to find one of the Sprague designs at a reasonable price is difficult though. The TEL-OHMIKE brings $175-$250 on Ebay and I wasn’t trying to spend quite that much. I started to look at other well known capacitor brands and landed on Cornell Dubilier’s BF-50 model. I managed to find the BF-50 fully functional and shipped to my door for less than $75!
The BF-50 allows you to test for the following:
- Open or Intermittent Capacitors
- Shorted Capacitors
- Leaky Capacitors
- Capacitance Value
- Grounded Capacitors
The BF-50 uses two transformers and two electron tubes. The 12A7 is the rectifier and the amplifier. The other is the 6E5 (“Magic Eye” ) which gives you the readings on the tests performed (listed above). The eye either opens/closes a specific amount or it will flash a specific amount per second to indicate the reading.